Introduction
          The pulp  and  paper  industry  converts  wood  or 
             recycled  fibre  into  pulp  and  primary  forms  of 
             paper. 
          In the 1800s, there was a shift away from using 
             cotton rags for paper production. Wood became 
             the most important source of fiber.
           
          First mechanical and then chemical methods have 
             been developed to produce pulp from wood. 
     Pulp and paper mills
     Pulp mills separate the fibres of wood or from 
      other  materials,  such  as  rags,  wastepaper  or 
      straw in order to create pulp.
     Paper  mills  primarily  are  engaged  in 
      manufacturing paper from wood pulp and other 
      fibre pulp, and may also manufacture converted 
      paper products. 
    Production process
      The production process can be divided into 7 
      sub-processes: 
    raw materials processes; 
    wood-yard;
    fibre line;
    chemical recovery;
    bleaching;
    paper production; 
    products and recycling.
      Simplified flow diagram of 
       integrated mill
           Pulping processes
               Pulping aims to separate cellulose fibers from 
               the wood structure.
                               Possible types of pulp production are:
                               
                                  Kraft (68%)
                               
                                  mechanical (22%) 
                               
                                  semi-chemical (4%) 
                               
                                  sulphite (4%) 
                               
    www.handprint.com             dissolving (2%).